Visceral Leishmaniasis

Visceral leishmaniasis (VL, kala azar) is a systemic infection of the reticuloendothelial system caused by Leishmania donovani complex (East Africa, Indian subcontinent) and L. infantum (Mediterranean, Latin America), transmitted by phlebotomine sandflies.

• About 50,000 to 90,000 new cases per year. In East Africa, key foci in South Sudan, Sudan, Ethiopia, Kenya (Baringo, West Pokot, Marsabit, Turkana, Wajir), and Somalia.
• Risk factors: malnutrition, HIV co-infection, and displacement.
• Fatal in over 95% of untreated cases. Post kala azar dermal leishmaniasis (PKDL) follows in 5 to 10% in the Indian subcontinent and up to 50% in Sudan.

• Prolonged irregular fever, progressive splenomegaly (massive), hepatomegaly, weight loss, pallor, and pancytopenia.
• Hypergammaglobulinaemia with hypoalbuminaemia, bleeding, secondary infections (pneumonia, tuberculosis, dysentery), and jaundice.
• Wasting with oedema, hyperpigmented skin (kala azar means black fever).
• Complications: haemophagocytic lymphohistiocytosis, relapse, and HIV-associated atypical disease.

• Rapid diagnostic test (rK39 immunochromatographic strip), with direct agglutination test (DAT); serology is less sensitive in HIV and East Africa.
• Parasitological confirmation: splenic aspirate (sensitivity above 95%), bone marrow aspirate (about 70 to 85%), or lymph node aspirate; PCR.
• Full blood count (pancytopenia), liver and renal function, albumin, HIV test.
• Exclude malaria, schistosomiasis, tropical splenomegaly, lymphoma, typhoid, brucellosis, TB, and leukaemia.

• East Africa first line: sodium stibogluconate (SSG) 20 mg/kg/day IM or IV plus paromomycin 15 mg/kg/day IM, both for 17 days.
• Liposomal amphotericin B (AmBisome): South Asia 10 mg/kg single dose; East Africa 3 to 5 mg/kg on days 1 to 5 and day 10 (total 30 mg/kg) when SSG-paromomycin not appropriate.
• HIV co-infection: liposomal amphotericin B 30 mg/kg total plus miltefosine 2.5 mg/kg/day (100 mg in adults over 45 kg) orally for 28 days; start antiretroviral therapy soon, then secondary prophylaxis (liposomal amphotericin B 3 to 5 mg/kg every 3 to 4 weeks) until CD4 above 200 cells/microL.
• Miltefosine 2.5 mg/kg/day for 28 days is an oral alternative (teratogenic; avoid in pregnancy; contraception for 5 months).
• Monitor for SSG toxicity (pancreatitis, cardiotoxicity, hepatotoxicity) and amphotericin B nephrotoxicity.
• Supportive care: blood transfusion, treatment of malnutrition, TB, malaria, and bacterial infections.
• PKDL: miltefosine 2.5 mg/kg/day for 12 weeks or liposomal amphotericin B.